170 research outputs found
An automated approach for classifying reverse-engineered and forward-engineered UML class diagrams
UML Class diagrams are commonly used to describe the designs of systems. Such designs can be used to guide the construction of software. In practice, we have identified two main types of using UML: i) FwCD refers to diagrams are hand-made as part of the forward-looking development process; ii) RECD refers to those diagrams that are reverse engineered from the source code; Recently, empirical studies in Software Engineering have started looking at open source projects. This enables the automated extraction and analysis of large sets of project-data. For researching the effects of UML modeling in open source projects, we need a way to automatically determine the way in which UML used in such projects. For this, we propose an automated classifier for deciding whether a diagram is an FwCD or an RECD. We present the construction of such a classifier by means of (supervised) machine learning algorithms. As part of its construction, we analyse which features are useful in classifying FwCD and RECD. By comparing different machine learning algorithms, we find that the Random Forest algorithm is the most suitable algorithm for our purpose. We evaluate the performance of the classifier on a test set of 999 class diagrams obtained from open source projects
Effect of Cutting Parameters on Surface Roughness in Dry Drilling of AISI D2 Tool Steel by Using Taguchi Method
Hard drilling of AISI D2 reportedly produce accelerated wear to the cutting tool that detrimental to the surface finish. This paper presents the effect of drilling tool and drilling parameters by using Taguchi method to produce minimum surface roughness under dry conditions. The experiments were conducted using high speed steel (HSS) based drilling tools, coated with various coating layer (uncoated, TiN and TiCN) on material AISI D2 tool steel. Two cutting parameters, spindle speed and feed rate, each at three levels were considered. An L9 array, the signal-to-noise (S/N) ratio and the analysis of variance (ANOVA) were employed to analyze the significant and percentage of each parameters for minimum surface roughness. The results revealed that the drilling tools gave main affects the surface roughness based on the highest percentage distribution (95%), followed by the spindle speed (3%) and feed rate (0.4%). Further, the results of ANOVA indicated that the combination of optimum parameter recorded as drilling tools HSS-TiCN with spindle speed of 680 rpm and feed rate of 206.25 mm/min
Evaluation of children with acute gastroenteritis in Konya region
Introduction: Acute gastroenteritis is a major cause of pediatric morbidity and mortality around the world. It remains a frequent reason for infection-related admissions to emergency units among all age groups. Epidemiologic knowledge about etiology of gastroenteritis in a certain area allows early and correct diagnosis. The current study aimed at evaluating the prevalence of bacterial, viral, and parasitic pathogens in children with gastroenteritis who admitted to pediatric emergency unit. Methods: The demographic, clinical and laboratory data of 450 children with acute gastroenteritis, within the age range of 0 months to 18 years who admitted to Pediatric Emergency Department of Meram Faculty of Medicine from September 2018 to September 2019 were retrospectively analyzed.Results: While 31.10% of the patients had etiological agents, 68.90% of the patients could not be identified. The identified pathogens were 2.10% bacteria, 82.20% virus, 15.70% parasite. The most common pathogen was Rotavirus with a rate of 72.90%. This was followed by E. histolytica with 15.00% and Adenovirus with 9.30%. Rotavirus was most frequently detected at the age of 2 years, and E. histolytica was most frequently detected at the age of 5 years. Rotavirus was most common in the winter season [33.7%]. 7.10% of the patients were hospitalized. The average length of hospital stay was 3.34 ± 2.19 days.Conclusion: Rotavirus, E. histolytica and Adenovirus were the most prevalent agents of diarrhea in children aged 0 month to 18 years who admitted to emergency unit in this study
Analysis of Surface Integrity and Formation of Material Side Flow in Dry and Wet Machining of Aluminum Alloy
This paper presents the surface integrity of aluminum alloy under dry and wet conditions. Bars of aluminum alloy with consistent size have been machined at different cutting speeds and feed rates at very short cutting time. The comparison between dry and wet cutting have been assessed based on the surface integrity, determined by the surface roughness value and observation of surface profiles. The result shows that machining in dry condition produces better surface finish where the coolants did not give a big impact on the surface roughness especially at the higher cutting speed. Further observation at the surface profile of dry cutting shows that more formation of material side flow appeared on the machined surface that could decreased the surface roughness value. Surface generated under bot dry and wet conditions appeared with well-defined and free from other damage such as cracking or tearing
Design for Manufacture And Assembly Analysis of Baby Stroller
This paper presents the study design analysis for manufacture and assembly (DFMA) of a baby stroller (Sweet Cherry SCR8 Series) in the aspect of part for manufacturing, assembly process and also handling and insertion difficulties. The problem identified in this study is on the features of the stroller that show a lot of fastener being used and also the usage of both hands in moving the fold latch to fold the stroller. The study has proven to save assembly time by 452.29s which is 23% more efficient than the original design. The number of parts reduced from 179 parts to be 149 parts. The DFA index is also improved from 9.6 to 12.6. The advantages of using DFMA method has been proved in the redesign of the baby stroller. Lastly, the analyzed results are discussed at the end of this research
Properties of Cement Brick Containing Expanded Polystyrene Beads (EPS) And Palm Oil Fuel Ash (POFA)
This paper assesses the mechanical properties of cement brick containing Expanded Polystyrene Beads (EPS) and Palm Oil Fuel Ash (POFA) as partial replacement of sand and Ordinary Portland Cement (OPC). The aim of this research are to determine the mechanical properties of brick containing EPS and POFA as partial replacement of sand and OPC. The dosage for EPS replacement is 20%, 30%, 40% and 50% EPS whereas 5%, 10%, 15%, 20% and 25% of POFA replacement. The mechanical properties of the bricks are density, compressive strength and water absorption. The bricks with 30%, 40% and 50% EPS replacement have density below 1680 kg/m3 which considered as lightweight brick. The brick with 50% EPS replacement recorded lowest density which is 1328 kg/m3 while 1629 kg/m3 for the brick with 25% POFA replacement at 56-days of curing. The water absorption testing for these brick are between 7.20%-18.19%. Brick with 0% POFA and 50% EPS replacement has the lowest water absorption properties whereas brick with 25% POFA and 0% EPS replacement has the highest water absorption properties
Initial Design of Semi Auto Soap Making Device from Used Cooking Oil for Home Appliances
This paper presents the comprehensive soap making device that can make soap from used cooking oil. The cooking oil can be converted to soap by using the mixture of used cooking oil, sodium hydroxide (NaOH) pellets, water and scented oil. The experiment was conducted to prove it. By having this right device, it will help users to carry out this converting used cooking oil to become a soap process more easily. They do not need to do this process manually. It can be used at a kitchen in every house. This device designed to raise the awareness the importance of recycling the cooking oil. Surveys has conducted with 50 public respondent, especially house wife. From the survey, it can be concluded that there are many people who dispose the used cooking oil to the place where should not be. The main objective of this paper is to discuss how to design a device to make soap from used cooking oil, to develop a functional prototype of soap making device from used cooking oil for home appliances and also to reduce pollution and increase environmental awareness towards Malaysians
Spike protein mutations and structural insights of pangolin lineage B.1.1.25 with implications for viral pathogenicity and ACE2 binding affinity
Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), the causative agent of COVID -19, is constantly evolving, requiring continuous genomic surveillance. In this study, we used whole-genome sequencing to investigate the genetic epidemiology of SARS-CoV-2 in Bangladesh, with particular emphasis on identifying dominant variants and associated mutations. We used high-throughput next-generation sequencing (NGS) to obtain DNA sequences from COVID-19 patient samples and compared these sequences to the Wuhan SARS-CoV-2 reference genome using the Global Initiative for Sharing All Influenza Data (GISAID). Our phylogenetic and mutational analyzes revealed that the majority (88%) of the samples belonged to the pangolin lineage B.1.1.25, whereas the remaining 11% were assigned to the parental lineage B.1.1. Two main mutations, D614G and P681R, were identified in the spike protein sequences of the samples. The D614G mutation, which is the most common, decreases S1 domain flexibility, whereas the P681R mutation may increase the severity of viral infections by increasing the binding affinity between the spike protein and the ACE2 receptor. We employed molecular modeling techniques, including protein modeling, molecular docking, and quantum mechanics/molecular mechanics (QM/MM) geometry optimization, to build and validate three-dimensional models of the S_D614G-ACE2 and S_P681R-ACE2 complexes from the predominant strains. The description of the binding mode and intermolecular contacts of the referenced systems suggests that the P681R mutation may be associated with increased viral pathogenicity in Bangladeshi patients due to enhanced electrostatic interactions between the mutant spike protein and the human ACE2 receptor, underscoring the importance of continuous genomic surveillance in the fight against COVID -19. Finally, the binding profile of the S_D614G-ACE2 and S_P681R-ACE2 complexes offer valuable insights to deeply understand the binding site characteristics that could help to develop antiviral therapeutics that inhibit protein–protein interactions between SARS-CoV-2 spike protein and human ACE2 receptor
Search for Higgs bosons decaying to tautau pairs in ppbar collisions at sqrt(s) = 1.96 TeV
We present a search for the production of neutral Higgs bosons decaying into
tautau pairs in ppbar collisions at a center-of-mass energy of 1.96 TeV. The
data, corresponding to an integrated luminosity of 5.4 fb-1, were collected by
the D0 experiment at the Fermilab Tevatron Collider. We set upper limits at the
95% C.L. on the product of production cross section and branching ratio for a
scalar resonance decaying into tautau pairs, and we then interpret these limits
as limits on the production of Higgs bosons in the minimal supersymmetric
standard model (MSSM) and as constraints in the MSSM parameter space.Comment: 7 pages, 5 figures, submitted to PL
Measurement of three-jet differential cross sections d sigma-3jet / d M-3jet in p anti-p collisions at sqrt(s)=1.96 TeV
We present the first measurement of the inclusive three-jet differential
cross section as a function of the invariant mass of the three jets with the
largest transverse momenta in an event in p anti-p collisions at sqrt(s) = 1.96
TeV. The measurement is made in different rapidity regions and for different
jet transverse momentum requirements and is based on a data set corresponding
to an integrated luminosity of 0.7 fb^{-1} collected with the D0 detector at
the Fermilab Tevatron Collider. The results are used to test the three-jet
matrix elements in perturbative QCD calculations at next-to-leading order in
the strong coupling constant. The data allow discrimination between
parametrizations of the parton distribution functions of the proton.Comment: 10 pages, 4 figures, 2 tables, submitted to Phys. Lett. B, corrected
chi2 values for NNPD
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